Real-Time Stress Development of Thin Si During Low-Energy Ion Bombardment by an In-Situ Optical Measurement Method

Observations of self-organized periodic patterns forming on solid material surfaces induced by ion beam irradiation have been long known. With continuing disagreement on the role of stress during ion beam nanopatterning, more consistent experimental measurements of stress are necessary. Multi-Optical Stress Sensor (MOSS) has been shown to be a reliable real time, in-situ technique to measure stress development in thin films from the resulting wafer curvature. Here, it is used to measure the stress development of the thin amorphized layer on the top of a Si wafer during room temperature Ar+ ion bombardment. In addition, the effect of removing the native oxide on the wafer is investigated. Resulting patterns on the Si surface are characterized by atomic force microscopy (AFM).